Structural Dynamics-Us最新文献_第5页

The role of transition dipole phase in atomic attosecond transient absorption from the multi-level model 跃迁偶极相在原子阿秒瞬态吸收中的作用

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-09-01 DOI: 10.1063/1.5124441

Guanglu Yuan, Shicheng Jiang, Zi-wei Wang, Weijie Hua, Chao Yu, C. Jin, R. Lu

Based on a multilevel model considering enough bound electronic states of atoms, we theoretically study the role of the transition dipole phase (TDP) in the attosecond transient absorption (ATA) spectrum of helium in intense laser fields. By solving the stationary Schrödinger equation with B-spline basis sets, we first calculate the transition dipole moments with well-defined phases between the bound states. Using the modified multilevel model, we reveal that the TDP plays an important role in determining the spectral structures if two or more paths populate the excited states from the ground state. Our multilevel model with the accurate TDP is convenient to address the origin of atomic ATA spectral structures by freely removing or adding specific electronic states and has been justified by comparing with the ATA spectra via directly solving the time-dependent Schrödinger equation. Hopefully, further incorporating macroscopic propagation into the model will provide indepth physical insights into experimental ATA spectra.

基于一个考虑原子足够束缚电子态的多级模型，我们从理论上研究了强激光场中氦的阿秒瞬态吸收光谱中过渡偶极相（TDP）的作用。通过用B样条基集求解平稳薛定谔方程，我们首先计算了束缚态之间具有明确相位的跃迁偶极矩。使用改进的多级模型，我们揭示了如果两个或多个路径从基态填充激发态，TDP在确定光谱结构中起着重要作用。我们的具有精确TDP的多级模型通过自由去除或添加特定电子态来方便地解决原子ATA光谱结构的起源，并通过直接求解含时薛定谔方程与ATA光谱进行比较来证明这一点。希望将宏观传播进一步纳入模型将为实验ATA光谱提供深入的物理见解。

引用次数: 6

Probing ultrafast C–Br bond fission in the UV photochemistry of bromoform with core-to-valence transient absorption spectroscopy 用核价瞬态吸收光谱探测溴仿紫外光化学中超快C-Br键裂变

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-09-01 DOI: 10.1063/1.5113798

Benjamin W. Toulson, M. Borgwardt, Han Wang, F. Lackner, A. Chatterley, C. D. Pemmaraju, D. Neumark, S. Leone, D. Prendergast, O. Gessner

UV pump–extreme UV (XUV) probe femtosecond transient absorption spectroscopy is used to study the 268 nm induced photodissociation dynamics of bromoform (CHBr3). Core-to-valence transitions at the Br(3d) absorption edge (∼70 eV) provide an atomic scale perspective of the reaction, sensitive to changes in the local valence electronic structure, with ultrafast time resolution. The XUV spectra track how the singly occupied molecular orbitals of transient electronic states develop throughout the C–Br bond fission, eventually forming radical Br and CHBr2 products. Complementary ab initio calculations of XUV spectral fingerprints are performed for transient atomic arrangements obtained from sampling excited-state molecular dynamics simulations. C–Br fission along an approximately CS symmetrical reaction pathway leads to a continuous change of electronic orbital characters and atomic arrangements. Two timescales dominate changes in the transient absorption spectra, reflecting the different characteristic motions of the light C and H atoms and the heavy Br atoms. Within the first 40 fs, distortion from C3v symmetry to form a quasiplanar CHBr2 by the displacement of the (light) CH moiety causes significant changes to the valence electronic structure. Displacement of the (heavy) Br atoms is delayed and requires up to ∼300 fs to form separate Br + CHBr2 products. We demonstrate that transitions between the valence-excited (initial) and valence + core-excited (final) state electronic configurations produced by XUV absorption are sensitive to the localization of valence orbitals during bond fission. The change in valence electron-core hole interaction provides a physical explanation for spectral shifts during the process of bond cleavage.

采用紫外泵浦-极紫外(XUV)探针飞秒瞬态吸收光谱研究了溴仿(CHBr3)在268 nm诱导下的光解动力学。Br(3d)吸收边(~ 70 eV)的核价跃迁提供了反应的原子尺度视角，对局部价电子结构的变化敏感，具有超快的时间分辨率。XUV光谱跟踪了瞬态电子态的单占据分子轨道如何在C-Br键裂变过程中发展，最终形成自由基Br和CHBr2产物。对从激发态分子动力学模拟中得到的瞬态原子排列进行了互补的从头计算。C-Br裂变沿着近似CS对称的反应路径，导致电子轨道特征和原子排列的连续变化。两个时间尺度主导了瞬态吸收光谱的变化，反映了轻的C、H原子和重的Br原子的不同特征运动。在前40秒内，由于(光)CH部分的位移，从C3v对称畸变形成准平面CHBr2，导致价电子结构发生显著变化。(重)Br原子的位移被延迟，形成单独的Br + CHBr2产物需要长达~ 300 fs。我们证明了由XUV吸收产生的价激发(初始)和价+核激发(最终)态电子构型之间的跃迁对键裂变过程中价轨道的局域化很敏感。价电子-核空穴相互作用的变化为键解理过程中的谱移提供了物理解释。

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引用次数: 14

Make the right measurement: Discovery of an allosteric inhibition site for p300-HAT 进行正确的测量：发现p300 HAT的变构抑制位点

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-09-01 DOI: 10.1063/1.5119336

A. Gardberg, Annissa J Huhn, R. Cummings, A. Bommi-Reddy, F. Poy, J. Setser, V. Vivat, F. Brucelle, Jonathan E. Wilson

Histone acetyltransferases (HATs) and histone deacetylases (HDACs) catalyze the dynamic and reversible acetylation of proteins, an epigenetic regulatory mechanism associated with multiple cancers. Indeed, HDAC inhibitors are already approved in the clinic. The HAT paralogs p300 and CREB-binding protein (CBP) have been implicated in human pathological conditions including several hematological malignancies and androgen receptor-positive prostate cancer. Others have reported CoA-competitive inhibitors of p300 and CBP with cell-based activity. Here, we describe 2 compounds, CPI-076 and CPI-090, discovered through p300-HAT high throughput screening screening, which inhibit p300-HAT via binding at an allosteric site. We present the high resolution (1.7 and 2.3 Å) co-crystal structures of these molecules bound to a previously undescribed allosteric site of p300-HAT. Derivatization yielded actionable structure-activity relationships, but the full-length enzymatic assay demonstrated that this allosteric HAT inhibitor series was artifactual, inhibiting only the HAT domain of p300 with no effect on the full-length enzyme.

组蛋白乙酰转移酶（HATs）和组蛋白脱乙酰酶（HDAC）催化蛋白质的动态和可逆乙酰化，这是一种与多种癌症相关的表观遗传学调控机制。事实上，HDAC抑制剂已经在临床上获得批准。HAT旁系基因p300和CREB-结合蛋白（CBP）与人类病理状况有关，包括几种血液系统恶性肿瘤和雄激素受体阳性前列腺癌症。其他人报道了具有细胞活性的p300和CBP的CoA竞争性抑制剂。在这里，我们描述了通过p300HAT高通量筛选发现的两种化合物，CPI-076和CPI-090，它们通过变构位点的结合抑制p300HAt。我们展示了高分辨率（1.7和2.3 Å）共晶结构结合到先前未描述的p300HAT变构位点。衍生产生了可操作的构效关系，但全长酶测定表明，该变构HAT抑制剂系列是人为的，仅抑制p300的HAT结构域，对全长酶没有影响。

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引用次数: 5

Effect of a bound anion on the structure and dynamics of halorhodopsin from Natronomonas pharaonis 结合阴离子对法老藻盐视紫红质结构和动力学的影响

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-09-01 DOI: 10.1063/1.5125621

M. Mizuno, Yumi Shimoo, H. Kandori, Y. Mizutani

Active ion transport across membranes is vital to maintaining the electrochemical gradients of ions in cells and is mediated by transmembrane proteins. Halorhodopsin (HR) functions as a light-driven inward pump for chloride ions. The protein contains all-trans-retinal bound to a specific lysine residue through a protonated Schiff base. Interaction between the bound chloride ion and the protonated Schiff base is crucial for ion transport because chloride ion movement is driven by the flipping of the protonated Schiff base upon photoisomerization. However, it remains unknown how this interaction evolves in the HR photocycle. Here, we addressed the effect of the bound anion on the structure and dynamics of HR from Natronomonas pharaonis in the early stage of the photocycle. Comparison of the chloride-bound, formate-bound, and anion-depleted forms provided insights into the interaction between the bound anion and the chromophore/protein moiety. In the unphotolyzed state, the bound anion affects the π-conjugation of the polyene chain and the hydrogen bond of the protonated Schiff base of the retinal chromophore. Picosecond time scale measurements showed that the band intensities of the W16 and W18 modes of the tryptophan residues decreased instantaneously upon photoexcitation of the formate-bound form. In contrast, these intensity decreases were delayed for the chloride-bound and anion-depleted forms. These observations suggest the stronger interactions of the bound formate ion with the retinal chromophore and the chromophore pocket. On the nanosecond to microsecond timescales, we found that the interaction between the protonated Schiff base and the bound ion is broken upon formation of the K intermediate and is recovered following translocation of the bound anion toward the protonated Schiff base in the L intermediate. Our results demonstrate that the hydrogen-bonding ability of the bound anion plays an essential role in the ion transport of light-driven anion pumps.

跨膜的主动离子传输对于维持细胞中离子的电化学梯度至关重要，并且是由跨膜蛋白介导的。盐视紫红质（HR）起到了光驱动的氯离子向内泵的作用。该蛋白质包含通过质子化的席夫碱与特定赖氨酸残基结合的所有反式视网膜。结合的氯离子和质子化的希夫碱之间的相互作用对离子传输至关重要，因为氯离子的运动是由质子化希夫碱在光异构化时的翻转驱动的。然而，这种相互作用在HR光循环中是如何演变的仍然是未知的。在这里，我们讨论了在光循环的早期阶段，结合阴离子对法老纳氏菌HR的结构和动力学的影响。氯化物结合、甲酸盐结合和阴离子贫化形式的比较提供了对结合阴离子和发色团/蛋白质部分之间相互作用的见解。在未光解状态下，结合的阴离子影响多烯链的π-共轭和视网膜发色团的质子化希夫碱的氢键。皮秒时标测量表明，在甲酸盐结合形式的光激发下，色氨酸残基的W16和W18模式的能带强度瞬间降低。相反，氯化物结合和阴离子贫化形式的这些强度降低被延迟。这些观察结果表明，结合的甲酸根离子与视网膜发色团和发色团口袋的相互作用更强。在纳秒到微秒的时间尺度上，我们发现质子化的希夫碱和结合离子之间的相互作用在K中间体形成时被破坏，并且在结合阴离子向L中间体中的质子化希夫碱转移后被恢复。我们的结果表明，结合阴离子的氢键能力在光驱动阴离子泵的离子传输中起着至关重要的作用。

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引用次数: 3

A versatile experimental system for tracking ultrafast chemical reactions with X-ray free-electron lasers 用X射线自由电子激光器跟踪超快化学反应的通用实验系统

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-09-01 DOI: 10.1063/1.5111795

T. Katayama, S. Nozawa, Y. Umena, Sung-Hak Lee, T. Togashi, S. Owada, M. Yabashi

An experimental system, SPINETT (SACLA Pump-probe INstrumEnt for Tracking Transient dynamics), dedicated for ultrafast pump-probe experiments using X-ray free-electron lasers has been developed. SPINETT consists of a chamber operated under 1 atm helium pressure, two Von Hamos spectrometers, and a large two-dimensional detector having a short work distance. This platform covers complementary X-ray techniques; one can perform time-resolved X-ray absorption spectroscopy, time-resolved X-ray emission spectroscopy, and time-resolved X-ray diffuse scattering. Two types of liquid injectors have been prepared for low-viscosity chemical solutions and for protein microcrystals embedded in a matrix. We performed a test experiment at SPring-8 Angstrom Compact free-electron LAser and demonstrated the capability of SPINETT to obtain the local electronic structure and geometrical information simultaneously.

已经开发了一个实验系统SPINETT（SACLA泵浦探针INstrumEnt用于跟踪瞬态动力学），专门用于使用X射线自由电子激光器的超快泵浦探针实验。SPINETT由一个在1 大气压氦气、两个Von Hamos光谱仪和一个工作距离短的大型二维探测器。该平台涵盖补充X射线技术；可以执行时间分辨的X射线吸收光谱、时间分辨的X-射线发射光谱和时间分辨的X-射线扩散散射。已经为低粘度化学溶液和嵌入基质中的蛋白质微晶制备了两种类型的液体注射器。我们在SPring-8 Angstrom Compact自由电子激光器上进行了测试实验，证明了SPINETT同时获得局部电子结构和几何信息的能力。

引用次数: 12

New insights and innovation from a million crystal structures in the Cambridge Structural Database. 剑桥结构数据库中一百万个晶体结构的新见解和创新。

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-08-28 eCollection Date: 2019-09-01 DOI: 10.1063/1.5116878

Jason C Cole, Seth Wiggin, Francesca Stanzione

The Cambridge Structural Database (CSD) is the world's largest and most comprehensive collection of organic, organometallic, and metal-organic crystal structure information. Analyses using the data have wide impact across the chemical sciences in allowing understanding of structural preferences. In this short review, we illustrate the more common methods by which CSD data influence molecular design. We show how more data could lead to more refined insights into the future using a simple example of trifluoromethylphenyl fragments, highlighting how with sufficient data one can build a reasonable model of geometric change in a chemical fragment with torsional rotation, and show some recent examples where the CSD has been used in conjunction with other methods to provide design ideas and more computationally tractable workflows for derivation of useful insights into structural design.

剑桥结构数据库（CSD）是世界上最大、最全面的有机、有机金属和金属有机晶体结构信息集合。使用这些数据进行的分析在理解结构偏好方面对整个化学科学产生了广泛的影响。在这篇简短的综述中，我们展示了CSD数据影响分子设计的更常见方法。我们用一个三氟甲基苯基片段的简单例子展示了更多的数据如何能够对未来产生更精细的见解，强调了如何在有足够数据的情况下，建立一个合理的扭转旋转化学片段几何变化模型，并展示了一些最近的例子，其中CSD已与其他方法结合使用，以提供设计思想和更易于计算的工作流程，从而导出对结构设计的有用见解。

引用次数: 12

Structure determination of the tetracene dimer in helium nanodroplets using femtosecond strong-field ionization. 飞秒强场电离法测定氦纳米液滴中丁烯二聚体的结构。

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-08-27 eCollection Date: 2019-07-01 DOI: 10.1063/1.5118005

Constant Schouder, Adam S Chatterley, Florent Calvo, Lars Christiansen, Henrik Stapelfeldt

Dimers of tetracene molecules are formed inside helium nanodroplets and identified through covariance analysis of the emission directions of kinetic tetracene cations stemming from femtosecond laser-induced Coulomb explosion. Next, the dimers are aligned in either one or three dimensions under field-free conditions by a nonresonant, moderately intense laser pulse. The experimental angular covariance maps of the tetracene ions are compared to calculated covariance maps for seven different dimer conformations and found to be consistent with four of these. Additional measurements of the alignment-dependent strong-field ionization yield of the dimer narrow the possible conformations down to either a slipped-parallel or parallel-slightly rotated structure. According to our quantum chemistry calculations, these are the two most stable gas-phase conformations of the dimer and one of them is favorable for singlet fission.

丁烯分子的二聚体在氦纳米液滴内形成，并通过对飞秒激光诱导的库仑爆炸产生的动力学丁烯阳离子发射方向的协方差分析进行识别。接下来，在无场条件下，通过非共振、中等强度的激光脉冲，在一维或三维上排列二聚体。将丁烯离子的实验角协方差图与七种不同二聚体构象的计算协方差图进行比较，发现与其中四种构象一致。二聚体的取向依赖性强场电离产率的额外测量将可能的构象缩小到滑动平行或平行轻微旋转的结构。根据我们的量子化学计算，这是二聚体最稳定的两种气相构象，其中一种有利于单线态裂变。

引用次数: 16

Exploring the multiparameter nature of EUV-visible wave mixing at the FERMI FEL. 探索FERMI FEL中EUV可见波混合的多参数性质。

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-07-29 eCollection Date: 2019-07-01 DOI: 10.1063/1.5111501

L Foglia, F Capotondi, H Höppner, A Gessini, L Giannessi, G Kurdi, I Lopez Quintas, C Masciovecchio, M Kiskinova, R Mincigrucci, D Naumenko, I P Nikolov, E Pedersoli, G M Rossi, A Simoncig, F Bencivenga

The rapid development of extreme ultraviolet (EUV) and x-ray ultrafast coherent light sources such as free electron lasers (FELs) has triggered the extension of wave-mixing techniques to short wavelengths. This class of experiments, based on the interaction of matter with multiple light pulses through the Nth order susceptibility, holds the promise of combining intrinsic ultrafast time resolution and background-free signal detection with nanometer spatial resolution and chemical specificity. A successful approach in this direction has been the combination of the unique characteristics of the seeded FEL FERMI with dedicated four-wave-mixing (FWM) setups, which leads to the demonstration of EUV-based transient grating (TG) spectroscopy. In this perspective paper, we discuss how the TG approach can be extended toward more general FWM spectroscopies by exploring the intrinsic multiparameter nature of nonlinear processes, which derives from the ability of controlling the properties of each field independently.

极紫外（EUV）和x射线超快相干光源（如自由电子激光器）的快速发展引发了波混频技术向短波长的扩展。这类实验基于物质与多个光脉冲通过N阶磁化率的相互作用，有望将固有的超快时间分辨率和无背景信号检测与纳米空间分辨率和化学特异性相结合。这方面的一个成功方法是将种子FEL FERMI的独特特性与专用的四波混频（FWM）装置相结合，从而展示了基于EUV的瞬态光栅（TG）光谱。在这篇前瞻性的论文中，我们讨论了如何通过探索非线性过程的内在多参数性质，将TG方法扩展到更通用的FWM光谱，这源于独立控制每个场的性质的能力。

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引用次数: 3

FACT and FAIR with Big Data allows objectivity in science: The view of crystallography 大数据的事实和公平使得科学客观:晶体学的观点

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-07-20 DOI: 10.1063/1.5124439

J. Helliwell

A publication is an important narrative of the work done and interpretations made by researchers securing a scientific discovery. As The Royal Society neatly states though, “Nullius in verba” (“Take nobody's word for it”), whereby the role of the underpinning data is paramount. Therefore, the objectivity that preserving that data within the article provides is due to readers being able to check the calculation decisions of the authors. But how to achieve full data archiving? This is the raw data archiving challenge, in size and need for correct metadata. Processed diffraction data and final derived molecular coordinates archiving in crystallography have achieved an exemplary state of the art relative to most fields. One can credit IUCr with developing exemplary peer review procedures, of narrative, underpinning structure factors and coordinate data and validation report, through its checkcif development and submission system introduced for Acta Cryst. C and subsequently developed for its other chemistry journals. The crystallographic databases likewise have achieved amazing success and sustainability these last 50 years or so. The wider science data scene is celebrating the FAIR data accord, namely, that data be Findable, Accessible, Interoperable, and Reusable [Wilkinson et al., “Comment: The FAIR guiding principles for scientific data management and stewardship,” Sci. Data 3, 160018 (2016)]. Some social scientists also emphasize more than FAIR being needed, the data should be “FACT,” which is an acronym meaning Fair, Accurate, Confidential, and Transparent [van der Aalst et al., “Responsible data science,” Bus Inf. Syst. Eng. 59(5), 311–313 (2017)], this being the issue of ensuring reproducibility not just reusability. (Confidentiality of data not likely being relevant to our data obviously.) Acta Cryst. B, C, E, and IUCrData are the closest I know to being both FACT and FAIR where I repeat for due emphasis: the narrative, the automatic “general” validation checks, and the underpinning data are checked thoroughly by subject specialists (i.e., the specialist referees). IUCr Journals are also the best that I know of for encouraging and then expediting the citation of the DOI for a raw diffraction dataset in a publication; examples can be found in IUCrJ, Acta Cryst D, and Acta Cryst F. The wish for a checkcif for raw diffraction data has been championed by the IUCr Diffraction Data Deposition Working Group and its successor, the IUCr Committee on Data.

出版物是对研究人员为确保科学发现所做工作和所做解释的重要叙述。然而，正如英国皇家学会巧妙地指出的那样，“Nullius in verba”（“不相信任何人的话”），即基础数据的作用至关重要。因此，在文章中保留这些数据所提供的客观性是因为读者能够检查作者的计算决策。但是如何实现完整的数据归档呢？这是原始数据归档的难题，在大小和对正确元数据的需求方面都是如此。晶体学中经过处理的衍射数据和最终导出的分子坐标存档已经实现了相对于大多数领域的示例性技术状态。通过为Acta Cryst引入的checkcif开发和提交系统，IUCr开发了示例性的同行评审程序，包括叙述、基础结构因素以及协调数据和验证报告。C，随后为其其他化学期刊开发。在过去的50年里，晶体学数据库同样取得了惊人的成功和可持续性更广泛的科学数据领域正在庆祝FAIR数据协议，即数据是可查找、可访问、可互操作和可重复使用的[Wilkinson等人，“评论：科学数据管理和管理的FAIR指导原则”，《科学数据》316018（2016）]。一些社会科学家还强调，除了需要FAIR之外，数据还应该是“FACT”，这是一个缩写词，意思是公平、准确、机密和透明[van der Aalst et al.，“负责任的数据科学”，Bus Inf.Syst.Eng.59（5），311-313（2017）]，这是确保再现性而不仅仅是可重用性的问题。（数据的保密性显然与我们的数据无关。）《晶体报》。B、 C、E和IUCrData是我所知道的最接近FACT和FAIR的数据，我在这里重复强调：叙述、自动“一般”验证检查和基础数据由主题专家（即专家裁判）彻底检查。IUCr期刊也是我所知道的最好的期刊，它鼓励并加快了出版物中原始衍射数据集的DOI引用；实例可在IUCrJ、Acta Cryst D和Acta Crystal F中找到。IUCr衍射数据沉积工作组及其继任者IUCr数据委员会一直支持对原始衍射数据进行核对。

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引用次数: 7

Time resolved transient circular dichroism spectroscopy using synchrotron natural polarization 同步加速器自然偏振的时间分辨瞬态圆二色光谱

IF 2.8 2区物理与天体物理 Q3 CHEMISTRY, PHYSICAL

Structural Dynamics-Us

Pub Date : 2019-07-02 DOI: 10.1063/1.5120346

François Auvray, D. Dennetiere, A. Giuliani, F. Jamme, F. Wien, B. Nay, S. Zirah, F. Polack, C. Menneglier, B. Lagarde, J. Hirst, M. Réfrégiers

Ultraviolet (UV) synchrotron radiation circular dichroism (SRCD) spectroscopy has made an important contribution to the determination and understanding of the structure of bio-molecules. In this paper, we report an innovative approach that we term time-resolved SRCD (tr-SRCD), which overcomes the limitations of current broadband UV SRCD setups. This technique allows accessing ultrafast time scales (down to nanoseconds), previously measurable only by other methods, such as infrared (IR), nuclear magnetic resonance (NMR), fluorescence and absorbance spectroscopies, and small angle X-ray scattering (SAXS). The tr-SRCD setup takes advantage of the natural polarization of the synchrotron radiation emitted by a bending magnet to record broadband UV CD faster than any current SRCD setup, improving the acquisition speed from 10 mHz to 130 Hz and the accessible temporal resolution by several orders of magnitude. We illustrate the new approach by following the isomer concentration changes of an azopeptide after a photoisomerization. This breakthrough in SRCD spectroscopy opens up a wide range of potential applications to the detailed characterization of biological processes, such as protein folding and protein-ligand binding.

紫外（UV）同步辐射圆二色性（SRCD）光谱对生物分子结构的测定和理解做出了重要贡献。在本文中，我们报告了一种创新的方法，我们称之为时间分辨SRCD（tr SRCD），它克服了当前宽带UV SRCD设置的局限性。这项技术允许访问超快的时间尺度（低至纳秒），以前只能通过其他方法测量，如红外（IR）、核磁共振（NMR）、荧光和吸收光谱以及小角度X射线散射（SAXS）。tr SRCD装置利用弯曲磁体发射的同步辐射的自然偏振，以比任何当前SRCD装置更快的速度记录宽带UV CD，将采集速度从10mHz提高到130 Hz和几个数量级的可访问时间分辨率。我们通过跟踪偶氮肽在光异构化后的异构体浓度变化来说明新方法。SRCD光谱的这一突破为生物过程的详细表征开辟了广泛的潜在应用，如蛋白质折叠和蛋白质配体结合。

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引用次数: 15